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Abstract

Tendencies of foodborne outbreaks show that the number of illnesses caused by Campylobacter spp. has been increasing recently in the European Union and in Hungary as well. However, the epidemiological statuses of Member States are diverse. There are several aspects to be investigated by competent authorities before the introduction of interventions. Methods supporting food safety decision making range from quick and easy techniques to complex, resource consuming approaches. The aim of the present study was the implementation of an evaluation and ranking system for a risk and its causes occurring in the broiler production chain. Data and information available in scientific literature were converted to a structured easy-to-use evaluation that supports decision making and helps structured data processing.

Open access

Abstract

The aim of this research was to assess the consumer habits of lactose sensitive persons in case of lactose-free products and their other shopping aspects for development of new, dairy-based lactose-free products. The research was based on face-to-face questionnaire survey, and those who declared to be lactose sensitive were analysed. Among them, only half of the women (49.3%) and one third of the men (34.6%) were medically proven lactose sensitive, so more than half of the respondents declared themselves affected on the basis of self-diagnosis. Our results show that reliably regular customers of lactose-free products are women and persons with medical diagnosis, high educational degree, and under the age of 30. The lactose-free consumer group prefers the following product features: lactose-free label; rich in calcium, vitamins, and fibre, and free of carbohydrate, sugar, and gluten. Only two-thirds of lactose sensitive customers (66.7%) consume lactose-free products regularly, so it can be assumed that the level of knowledge of this disease, its treatment, and the importance of lactose-free dairy products among these persons is insufficient. This could be solved with education, advertisement, and other information opportunities.

Open access

Abstract

The aim of this research was to study the effect of micro- and industrial scale malting on the folate content of barley. Two malting barley varieties (one spring and one winter) were studied, applying the same technology. Furthermore, a roasting experiment was carried out at given temperatures for different time periods. The total folate content was determined by microbiological method. The folate content of the barleys was between 10.1 and 23.4 µg/100 g dry matter. For micro- and industrial scale, malting folate content increased 6.5–8-fold and 4–7-fold, respectively, during the malting process. An unexpected result was observed during industrial malting: the folate content increased during kilning by 18–35%, unlike micro scale malting, where a 15–20% decrease was observed. Results obtained during roasting showed that folic acid content did not decrease when roasted for 20 min at 100 °C, but it decreased linearly with increasing temperature. Folate is completely degraded in 20 min at 200 °C. It can be stated that barley malt can serve as a relatively good source of folate, but barley variety and malting technology have significant impact on it.

Open access

Abstract

Brown rice was germinated for different times (12, 24, 36, and 48 h) at different temperatures (25, 30, and 35 °C) with the aim to improve the in vitro digestibility and antioxidant potential of the flour made from it. Results showed that increase in germination time and temperature increased in vitro digestibility of starch and protein during germination of brown rice owing to depolymerisation of starch and protein molecules by enzymatic activity. After germination under varying conditions, antioxidant activity increased from 50.19 to 95.58%, total phenolic and flavonoid contents from 0.88 to 2.02 mg GAE/g and 34.06–62.94 mg QE/100g, respectively. Germination at elevated temperature (35 °C) for prolonged time (48 h) also increased the reducing power by 60.49% and metal chelating activity by 114.50% as a result of structural breakdown of bound phenolics. Increased activity of hydrolytic enzymes with progress in the germination time and temperature also results in continuous reduction in the pasting properties and lightness values (L), while increasing a* and b* values of the flour of germinated brown rice. Tailored germination, therefore, can be offered as a tool to increase nutrient digestibility and bioactive potential of brown rice as compared to non-germinated brown rice, thus, producing naturally modified flour with enhanced functionality.

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ABSTRACT

Cherry tomatoes inoculated with Escherichia coli O157:H7 and Salmonella Typhimurium were treated with vaporised ethyl pyruvate (EP). The changes of microbial and organoleptic properties of the samples during storage were investigated at two temperatures (4 and 10 °C) and four EP concentrations (0, 42, 105, and 420 ppm) for 7 days at 4 °C and for 5 days 10 °C. After 3 days, 4.3 log and 3.6 log reductions in E. coli O157:H7 numbers were detected in cherry tomatoes treated with 42 ppm EP at 4 °C and at 10 °C, respectively. The highest EP treatment (420 ppm) led to 5.7 log CFU g−1 E. coli O157:H7 reduction after 1 day at 4 and 10 °C. The reduction of Salmonella Typhimurium on samples treated with 420 ppm EP was 7.7 log CFU g–1 after 1 day at 4 °C, and 6.9 log after 1 day at 10 °C. The treatment of EP can be effective at decreasing pathogen populations and can protect the organoleptic and colour properties of fresh produce.

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Abstract

The objective of this study was to use matrix-assisted laser desorption ionisation–time of flight mass spectrometry (MALDI-TOF MS) for the identification of ovine-associated staphylococci. Presumptive Staphylococcus isolates were recovered from ovine udder surface (US), individual raw milk, bulk tank milk, and cheese samples and were characterised by conventional phenotypic methods. A total of 69 bacterial isolates were further confirmed by MALDI-TOF MS. Forty-two (60.9%) of 69 isolates were successfully identified on genus and species level. Two thirds (n = 28) of the 42 identified isolates were shown to be Staphylococcus spp. These 28 staphylococcal isolates formed two clusters, one consisting of 22 Staphylococcus aureus strains and the other composed of 6 non-aureus staphylococci, including S. simulans (n = 3), S. auricularis, S. equorum, and S. haemolyticus. MALDI-TOF MS has proven to be a reliable tool for the identification of staphylococci from raw sheep's milk, especially bulk tank milk; however, currently it appears to be less useful for the identification of bacterial isolates originating from ovine US samples. This is the first study to evaluate the applicability of MALDI-TOF MS for identification of Staphylococcus spp. in ovine raw milk, cheese, and US samples in Hungary.

Open access

Abstract

In this study, the potential of the substitution of the conventional preservative potassium sorbate by fermented wheat flour as an alternative was analysed. The organic acid content and antibacterial activity of preservatives and the macronutrient characterisation were tested, as was the sensory evaluation of biscuits with added conventional and alternative preservatives. The results show that the fermented wheat flour contains secondary fermentation metabolites (e.g. acetic, lactic and pyruvic acids). Both fermented wheat flour and potassium sorbate have antibacterial effects against Staphylococcus aureus, Bacillus cereus and Bacillus subtilis. The sensory evaluation demonstrated that fermented wheat flour in the recommended concentration range had no impact on sensory quality. Therefore, fermented wheat flour represents a potential substitution for conventional potassium in bakery products.

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Land use change may modify key soil attributes, influencing the capacity of soil to maintain ecological functions. Understanding the effects of land use types (LUTs) on soil properties is, therefore, crucial for the sustainable utilization of soil resources. This study aims to investigate the impact of LUT on primary soil properties. Composite soil samples from eight sampling points per LUT (forest, grassland, and arable land) were taken from the top 25 cm of the soil in October 2019. The following soil physicochemical parameters were investigated according to standard protocols: soil organic matter (SOM), pH, soil moisture, NH4 +–N, NO3 –N, AL-K2O, AL-P2O5, CaCO3, E4/E6, cation exchange capacity (CEC), base saturation (BS), and exchangeable bases (Ca2+, Mg2+, K+, and Na+). Furthermore, soil microbial respiration (SMR) was determined based on basal respiration method. The results indicated that most of the investigated soil properties showed significant difference across LUTs, among which NO3 –N, total N, and K2O were profoundly affected by LUT (p ≤ 0.001). On the other hand, CEC, soil moisture, and Na+ did not greatly change among the LUTs (p ≥ 0.05). Arable soils showed the lowest SOM content and available nitrogen but the highest content of P2O5 and CaCO3. SMR was considerably higher in grassland compared to arable land and forest, respectively. The study found a positive correlation between soil moisture (r = 0.67; p < 0.01), Mg2+ (r = 0.61; p < 0.01), and K2O (r = 0.58; p < 0.05) with SMR. Overall, the study highlighted that agricultural practices in the study area induced SOM and available nitrogen reduction. Grassland soils were more favorable for microbial activity.

Open access

Abstract

Presence of pathogenic strains of Escherichia coli in foodstuffs may pose a health risk for a consumer. Therefore, knowledge on the effect of environmental factors on the growth ability of E. coli is of great importance. In this work, the effect of incubation temperature (6–46 °C) and the combined effect of temperature and water activity (0.991–0.930) on the growth dynamic of E. coli PSII were analysed. Based on the growth curves obtained, growth parameters were calculated by using the Baranyi D-model. Growth parameters were further analysed in secondary phase of predictive modelling. Using the CM model that describes the effect of combined factors, cardinal values (T min = 4.8 ± 0.4 °C, T opt = 41.1 ± 0.8 °C, T max = 48.3 ± 0.9 °C, a wmin = 0.932 ± 0.001, and a wopt = 0.997 ± 0.003) for the isolate were calculated. Under optimal conditions, the specific growth rate is µ opt = 2.84 ± 0.08 h−1. The results obtained may contribute to the assessment of the risk associated with the possible E. coli presence in raw materials and to the search for preventive measures with defined degree of accuracy and reliability.

Open access

Abstract

In this study, the hygienic handling of leafy vegetables was evaluated in ten selected food establishments located in south-eastern Brazil. A 14-question survey was applied in these establishments, addressing the origin of the vegetables, washing procedures, and temperature conditions during storage and exposure. In addition, 30 samples of leafy vegetables were collected and submitted to the enumeration of total coliforms, coliforms at 45 °C and tested for Salmonella. Based on the responses to the survey, the establishments could be clustered into three groups. Group 1 included four establishments, where the vegetables originated from farms exclusively and were displayed to consumers at room temperature, and where most of the food handlers had participated in courses on good handling practices. Group 2 included two establishments that performed a centrifugation step and where vegetables were not available to consumers in a self-service. Finally, group 3 included four establishments, where vegetables originated from suppliers exclusively, were stored under refrigeration, and displayed to consumers on refrigerated tables. The mean count of total coliforms was 2.5 ± 0.7 log MPN/g, while coliforms at 45 °C were detected in only one sample (0.9 log MPN/g). Salmonella was not found in any sample. Microbiological results obtained for leafy vegetables from establishments clustered in the three groups did not differ significantly. These data contribute to a better understanding of the hygienic handling of leafy vegetables in the surveyed Brazilian food establishments.

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